isopleth

noun

iso·pleth ˈī-sə-ˌpleth

1

: an isoline on a graph showing the occurrence or frequency of a phenomenon as a function of two variables

2

: a line on a map connecting points at which a given variable has a specified constant value

isoplethic

ˌī-sə-ˈple-thik

adjective

Word History

Etymology

International Scientific Vocabulary is- + Greek plēthos quantity; akin to Greek plēthein to be full — more at full

First Known Use

1908, in the meaning defined at sense 1

Time Traveler

The first known use of isopleth was in 1908

See more words from the same year

Cite this Entry

Style

“Isopleth.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/isopleth. Accessed 31 Oct. 2025.

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